1972
++ TR-33
++ TR-55 (see Acetone FR-6)
++ TR-77 (Acetone FR-8L)
The TR stands for Transistor Rhythm. These were the first Roland-branded products.
The 77 is known as an updated version of Ace Tone Rhythm Ace FR-8L. It is also known as Hammond Rhythm Unit.

1996MC-303 Groove box.
This was Roland’s first entry into the club and DJ scene; it became a new hit in the world of dance music. It was their first non-keyboard drum machine, sample-based synthesizer, and sequencer combination bearing the name Groovebox. Supporting a full 8-track sequencer.